Abstract: The accurate delineation of radiotherapy planning target volume (PTV) for glioma is always the pursuit of the clinicians. Nowadays the radiotherapy technology is quickly developing, from previous physical modulated intensity radiotherapy to biological modulated intensity radiotherapy, accordingly the accurate delineation of PTV is becoming more and more important. This review will introduce the value and significance of PET in definition of PTV and BTV (biology target volume) and discuss the respective value of different tracer for target volume presentation.